Casts

Hyaline Cast

·        Most frequently seen

·        Consists almost entirely of uromodulin

·        Normal: 0-2/lpf

·        Pink in Sternheimer-Malbin stain

·        Glomerulonephritis

·        Pyelonephritis

·        Chronic renal disease

·        CONGESTIVE HEART FAILURE

·        Stress and exercise

RBC Casts

·        Associated with damage to GLOMERULUS

·        Glomerulonephritis

·        Stress and exercise

WBC Casts

·        Infection or inflammation within the nephron

·        Associated with PYELONEPHRITIS

·        Primary marker for distinguishing pyelonephritis from cystitis

·        Pyelonephritis: upper UTI (WBC casts, WBCs, Bacteria

·        Cystitis: lower UTI (WBCs, Bacteria)

·        Acute interstitial nephritis: WBC casts only

·        Pyelonephritis

·        Acute interstitial nephritis

Bacterial casts

·        Containing bacilli both within and bound to the protein matrix are seen in pyelonephritis

·        Pyelonephritis

Epithelial cell casts

·        Casts containing RTE cells represent the presence of advanced tubular destruction producing urinary stasis along with disruption of the tubular linings

·        Similar to RTE cells, they are associated with heavy metal and chemical or drug-induced toxicity, viral infections and allograft rejection

·        Renal tubular damage

Coarse/Fine granular casts

·        Coarsely and finely granular casts are frequently seen in the urinary sediment and may be of pathologic or non-pathologic significance

·        Glomerulonephritis

·        Pyelonephritis

·        Stress and exercise (HC, GC, RC)

Fatty casts

·        Fatty casts are seen in conjunction with oval fat bodies and free droplets in disorders causing lipiduria

·        Fats do not stain with Sternheimer-Malbin stain

·        Confirmation by polarized microscopy and Sudan III or Oil Red O fat stains

·        Nephrotic syndrome

·        Toxic tubular necrosis

·        Diabetes mellitus

·        Crush injuries

Waxy casts

·        Representative of extreme urine stasis, including chronic renal failure

·        Associated with the condition that has caused the renal failure often appear fragmented with jagged ends and have notches

·        Stasis of urine flow

·        Chronic renal failure

Broad casts

·        Often referred to as renal failure casts

·        All types of casts may occur in the BROAD form

·        Most commonly seen broad casts are GRANULAR and WAXY

·        Extreme urine stasis

·        Renal failure